MONITORING SYSTEM

A monitoring system includes monitoring devices provided in a monitored device and monitoring the monitored device, and a controller that wirelessly communicates with the monitoring devices to acquire monitoring information of the monitored device from the monitoring devices. The monitored device is switchable between an operating state and a non-operating state. In the non-operating state of the monitored device, the monitoring devices establish communication connections in which at least one of the monitoring devices acts as a communication master and others of the monitoring devices act as communication slaves for the communication master. In the non-operating state of the monitored device, the controller does not act as a communication master for the monitoring devices.